Pneumatic tool.



- PATENTED DEC. 4, 1906. H. LEINEWEBER.

PNEUMATIG T0013'.v

ABPLIOATION FILED A'UG.27, 1906.

- mmllll and-'viewed as indicated by arrows', Fig. 7, av

. UNITED. STATES .PyrEisrr` onirica.

HERMAN'LEiNEvirEBEm-or SoU'ri'i'- cH'icAeo, ILLINOIS; Assicivon or y ,5 oNE-HALFTO.WILLIAMM. BAYNE, or CHICAGO, iLLiNois.

- Prweulyuirlc:Tool...

i Tfallwhbm it Maginon/eerie.:

f Beit knownth'atFLHERMAN LEINEWEBER,

aciti'zen of the` United States', residing at South Chicago, in the county Cook-and` A'State of Illinois, have invented a new and 'fuseful Improvement in Pneumatic Tools, of-

" f which the following is a specification.

My invention relates to improvement inl the class of valvelesspneumatic toolsemfro' 'ployinga reciprocating piston-hammer ac- "f tuated against. the tool proper by air-presl sure centrally'introduce'd alternatelyl against .fl'the ends of thepistonfby way of air-cham- Jfb'ers provided at its opposite ends in the '15 casin t The primary object of my invention ist'oy overcome a defect' in tools of the class referred to, which consists in the tendency of the. 'piston,fwhen the tool is laid aside or its "2q operation is interrupted, toattain the f deadpoint 'in the casing, which renders the starting of its o eration more or less difficult. Thistendency is dueto rac'tically unavoidlableleakage pastv the-'piston of air-pressure between the aforesaid air-cliambers,'whereby the pressure. becomes equalized in both chambers, causing the piston to seek the midway or dead-point position between M them.

l' "3o. A .further Object 0f my invention is to im Referring to the accompanying drawings, 'Eignre, 1 is a longitudinal section ofv a pneu- .maticltool embodying my invention. Figs. wlgtn, and 6 are section taken, 4respec- 1 y aethe 1ines 2, 3,*v 4, 5, and c on Fig. i

view inelevation of the duct ,containing '..llshing for the valve which controls theadmission of air-pressure to the tool andFlg 8 a vsection taken Aat theline 8 on Fig. 7 and y v ieviffedfin the directionof; the arrow. The, casing 9 hasinserted into ,one end the desired rtool proper, 10, s'h`o\vn broken,- and' igcontains the air-chambers 11a'nd'12 in itsA Him-opposite end portions, art of the casing shown being the hollow ead 13, forming the larger chamber 12 and provided on its outerV closed end witha centralhollow boss 14,for

fcushi'oning the Vbackstroke of thev piston-f1.5.

'Specification of Letters Patent.

j Appiimionled'iggm27,190s; Serial 110.332.124. v

Patented nec. 4,1906.;

and the tool-handle 16 is on this head.' A155 housing 1.7 is formed to extend diametrically. across the closed end of the head ortion 13 of thecasing adjacent to the hand e and terminates at one end ina restricted extension l18, commun'icating with the nipple 1 9, to which' is attachable the usual flexible tube (not shown) for sup lyingthe operating'airpressure to the imp ement.J Y

Near the opposite end of the housing 17,

adjacent to' which isfulcrumed the thumblever or trigger 20, is provided a port 21 in the chamber-wall, registeringfwith an airpassage "22, formed longitudinally in the'wall of the casing-head and which is closedat-it forward end, adjacent to which it 'is expand'- ed inwardly to form the lateral extension 23, which leads to and covers a plurality of airinlet` passages 24, extending longitudinally in the casing-wall to an annular pressurefeeding chamber 25,*formed about the interior of saidwall. A Series of exhaust-ports 26 (shown as five in number) -radiate throughthe casingwall near the chamberV 12, andsimilar 'exhaust-ports. 27, of which four are shown, are provided in the casing near the 8o chamber 11. The piston 15, which recipro-V. vcates between the boss 14 and the stem of the tool 10,is closed at both-ends and contains a desired number of ducts 29, each terminating at'its opposite ends, respectively, in lateral 'openings 30 and l31 in the piston near its ends. The parts thus far described present no features of novelty, but afford a' desirable, though not-the only construction, with which to employ my improvements hereinafter described. f

a In the housing'17 is rigidly confined a tubular'bushing 32', o enat its end nearest the. lever 20, buty close at its opposite end, eirlcept for two -grooves 33 34, formed longitudinally in op osite sides of its wall to produce withthe wall of the surrounding housing' (of which the bushing forms a lining and is to all intents vandl purposes .a part) air-ducts' communicating at one end with the nipple 19 andterminatin vat their opposite ends in ports 35, forme throughthe bushing to conneet the ducts'jwith the interior thereof, and similar 'ort's 3 6 extend transversely fromthe ductstlir yond the center of thebjosslt, adjacent to a pieyided at saidlpfnter in the bushough the Walla-'ef the'v bushing 'beducts throughv the-ports 21et and 21, passage 22, and passage 24 into-the teeding- .r

' piston.

withv the port 37, which is in the nature ot a wlorking the piston.

terential recess 40 adjacent to that iead 'end'sof the piston-ducts, passes through the chamber 1 1' or 12, as the case may be. Should ing-wall and' opening into the pressurechamber 12. Another' vport 21a is provided in the wallof the bushing at a point lto register with the port 21. Within the bushing is reciprocablyconiined a spring-pressed closelyfitting solid cylindrical valve 38, having a head 39 adjacent to the trigger 20., a circumhead 41 on ,its opposite end against which its controlling-spring 42 is confined, and adjacent to the last-named head 41 a circumferential recess 40, normally registering with, the por-ts 36;

To operate the tool, supposing tre piston tobe in its most` advanced position= to start" with, pressure'onthe trigger 20 moves tifo valve 38 against the resistance of thespring with the event-ual effect of registering tfje recess 40 with the ports 35, whereby communication is establishedl of the ducts 33 34 with the port 21a, registering with recess, and air-pressure may thus pass homthe amber 25 to enter the rear ends of the piston-ducts 29andpassing throughl the latter reach the chamber 11- for driving the iston back-ward,- whereupon the pressure-fee from the chamber 25, then registering with the 4forward latter-into the chamber 12 to -exert tile force for driving the piston forward'` As the pistonclears the exhaust-ports near -itsjopposite endsthepressure exhausts from the adjacent the piston, however, occupy the cent-ral deadpointposit-ion referred to, it must tobe operated be preparatorily actuated to tiieend of its stroke, else, obviously, the pressiue-supply from the feeding-chamber 25 to either power-chamber 11- or 1-2 is closed by tite The described valve construction servesto pre aratorily drive the piston to the end of its torward stroke, since'in moving the vvalve by manipulating the trigger 20 the recess 40l is first brought into registration supplemental port, since it permits the airressure fed to that recess to ent er the chamer 12l and-supplement the pressure already that chamber to act against the piston and drive-it forward by overcoming the pressure at itsimpact end in the chamber l1.' As in theinward movement ofthe valve tite recess 40@ clears the ports 'the. valve closes them,

and the-recess 40 is brought .into registrai ion with the ports to admit from the ducts 33 34 the-pressure to the port 21a-for regularl)Y lli/when the operator releases the trigger, the valve resumes under the pressure ot thespring 42 the normal position iirwhich yit is illustrated ser,

Ahousing containing a supplemental thirty-second of an inch, than are the ports 35 to the corresponding end of the recess 4U, so that in the inward movement of the valve the ports v36 will be about half closed betore the ports 35 'are opened, and that the arrange-ment of parts is such as to simultaneously register the ports 37 and 21, respectively, withthe recesses 40a and 40.

About the .inner wall ofthe chamber 11, preferably midway between the shoulder 43 and the bearing 44 for the 4tool-stern, is formed an annular guide-bearing 45 of a diameter to'h't around the'piston and provided at' intervals with transverse slots 46 teatford communication vbetween the parts of the chamber 11 at its opposite sides 'when 4 the piston is within the bearing 45. Where the fit of the piston' in the section yof the casing snugly surrounding it is inaccurate or becomes impaired, the extent of its projection iin-making the forward -stroke beyond th shoulder 43 tends to render it wabbly, with theeffeot of 'increasing tlie'vvear upon it. This is prevented `by the piston working through the guide-bearing, which serves to shorten the space in which it is'unsupperted in passing through the chamber 1=1 and to sustain. and guide it. l

by Letters lPatent', is- 1. In a pneumatic tool, the. combination ,of a casing carrying at one end the tool, a reciprocating pistonl -inthe casing, a'i'r-chan1- bers in the opposite ends of said casing, between which thel piston works, one of said chambers having asupplomental inlet-port connnunicating'with the suppljr of air-pressure for reciprocating the piston, and a valve controlling said communication, for the purpose set forth,-

2. In a `pneumatic tool, the combination of a casing carrying at one end the 'toch a reciprocable piston in the casing,vair cha1 i i bers inthe opposite ends of said casing, hetween which the piston works, a housing having a'suppleinental portleadinur into the rear end chamber and through whichtheair pressure is supplied to said chambers' for reciprocating the piston, and a valve in said .housing controlling eonnnunication therewith through said supplemental port, for the purpose set forth.

I'na 'pneumatic tool, the combination of a casing carrying at one end the tool, a ref ciprocable piston in the casing, air-chambers in the opposite ends of said casing, hetween which the piston works, a housing on the outer wall of the rear chamber through which the air-pressure is supplied to the chambers for reciprocating the pist iii,said port through which it communicates with said It will be observed that with the valve 3S in its normal position the ports 36 are nearer l the upper end of the recess 40, say, by one rear chamber, and a valve in the housing controlling said communication, for the purpose set forth.

'What I claim as new, andv desire to secure 4. In a pneumatic'tool, the combination of if; a casing 'carrying at one endthe tool a recipro-.

Vcable piston in the casing7 air-chambers in` l `'the opposite ends of said casing, between which the piston works, a housing extending across the outer walliof the rear chamber and through one end of which the air-pressure is' supplied to the chambers for reciprocating the piston, said housing containing a .port

through which it communicates with said rear chamber, la sprin fpressed valve reciprocably conned in the ousing and controllin said communication, and a'trigger supported on the casing to engage said valve,for the purpose set `forth.

5. In a pneumatic tool, the combination of.

a cas'ing'carrying at oneend the tool, a recip- *rocable piston in the casing, air-,chambers in Vthe opposite ends of said casing, between which the pistonv works, a housing extending A across the outer wall ofthe rear chamber and adapted-to be connected at one end with .the

supply of -air-pressure to said chambers through the piston7 for reciprocating it, said housing containing a longitudinal duct lead` ing from said end and ports at different points along'its length connecting said duct with the interior of the housing, ports -leading through the--housing-wall respectively into said rear chamber and to the passagesinv the implement through which air-pressure is introduced in to said chambers to reciprocate the piston, a spring-pressed valve reciprocably confined in the housing and having recesses to register with said ports leading from the housing through its wall'and with the ports leading from said ducts into the interior of the housing-'and a trigger supported on the casing to engage said valve,'for the purpose set forth.

' pi 6. Ina` pneumatic tool, the com ination of a casing carrymg at one end the too a reciprothe opposite ends of sai casing7 between which the piston works, a housing extending across the'outer-wall ofthe rear chamber, a bushing in said housing adapted to be connectto said chambers throng i the piston for reciprocating it, said' bushin containing, in opposite sides, longtudina grooves -orming and containing port's into which said ducts ports leading through the bushingwall respectively into said rear chambers and to thel passages in the implement through wln'ch reciprocate the piston, va spring-pressed cy* lindrical valve reciprocably confined in the said ports leading from the bushing through its wall and with portsleading'from said ducts into the interior vof the bushing, and a trigger supported on the casing to engage said valve, for the purpose set forth.

7. In a pneumatic tool, the combination of a casing carrying at one end the Atool and convpiston confined in the casing to be recipro- 4cated therein by 'airepressure introduced alternatelyl into said chambers a ainst the pisthe casing in the vforward chamber between its ends7 said ring being slotted to permit communication through it of the parts ot the chamber at its opposite sides, for the purpose set forth.

HERMAN In presence of'-- L. HEISLAR, l1; J. H. LANDEs.

L nr'Niivvninnav air-pressure is introduced to'said chambers to --cating piston in the casin air-chambers in ed at one end with the su plT 'of air-,pressure 1 with the housing ducts leadingffrom said end open at different points in the `bushing-wall,

ton ends, and a guide-bearing or the piston, consisting of'a ring about the inner Wall of 

